Researchers at Johns Hopkins University's Center for Addiction and Pregnancy in Baltimore said many substance abuse programs often fail to address cigarette smoking despite the clear risks to both mother and fetus -- including ectopic pregnancy, spontaneous abortion, preterm delivery, low-birth weight and Sudden Infant Death Syndrome.

One of the most effective methods of helping people quit smoking is contingency management, which gives smokers monetary incentives for meeting target goals, the researchers said.

More than 100 pregnant smokers who were prescribed methadone maintenance for heroin dependence were enrolled in a study comparing three conditions.

One-third of the women received escalating monetary incentives for reducing their level of cigarette smoking or by being abstinent, as measured by breath carbon monoxide levels; one-third earned incentives for reduced smoking; and one-third received information about the risks of smoking during pregnancy, but no money.

Nearly half of the contingency management women -- who received money for reducing smoking until total abstinence by week 12 -- met the target of 75 percent reduction at least once, and one-third of them met criteria for 100 percent smoking abstinence at least once by week 12.

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